Milling cutter



Apri|26,1932. J EDGAR 1,855,511

MILLING CUTTER Filed July 16, 1924 JOHN nncnnvorvnocnronn, ILLINOIS, AssIGNonfro isARBER-COLMAN Patented Apr. 26, 1932 f MILLING UTIER t Appueatioii sie@ Iniy 1e,

The invention has particular reference-to milling cutters of the inserted toothptype, Vand it has for its general object the provision of such a cutter wherein --the inserted blades forming the teeth may be etlectually secured about the cutterv body in' closely spaced Vrelation, so as to renderV it' pos-sible'to provide a large number'of blades for the cutter. 'g

More specifically stated, one object of the, invention is to provide an improved 'means for clamping the blades imposition in vthe cutter body, each such, means serving to clamp two adjacent blades so thatthe body-space occupied bythe securing means is yreduced p f intothe slots 17, but theflatter to a minimum. l

A further object is tof providev a blade tsecuring means including clampingy members having wedge surfaces on their opposite sides adaptedto coact with the opposed faces of two adjacent blades so that by tightening one securing means the clamping of two blades is eli'ected.

In the accompanying drawings thereis i 5 shown a rotary milling cutter having toothed blades inserted accordingto this invention. For the purpose of illustration, I have shown a milling cutter having helically `arranged teeth suitable for milling gears.

Figure 1 is a fragmentary side view of a large milling cutter. j j

Fig. 2 is a view of the cuttingV faceof 4the cutter in Fig. 1. n Y .A n

Fig. 3 is a cross sectionalview on the line 3-3 of Fig. 4. n p

along the line Fig. 4 is a sectional view of Fig. 3.

Fig. 5 is a detailed view ture employed. 1 A

In the drawings the cutter body is shownas comprising a main annular portion 10 into which blades 11 are inserted. `A web 12 is formed within the annular portion 10 ofthe body and carries a hub portion 13'which is adapted for mounting the cutter asbythe provision of suitable bolt holesr14. The web 12, it will be observed from Fig. 4, is `made of a thickness substantially less 'than the rim portion 10, so that annular shoulders 15`andk 16 are provided on opposite sides of thebody. To receive the blades 11 the cutter body is of the wedgel strucriphery of Vthe cutter,

1924. seiiaint. rasees. e

provided with slots 17 arranged vtransversely j coMPA'Ni-r, lor Rockman, ILLINOIS, A-coRronArrIoN or ILLINOIS. V i f" of its peripheral surface and inapproximate-vy ly equidistantly spaced relation. shown clearly in Fig. 3, these ,slots are inclined slightlyforwardly in the ,direction ofrota tion ofthe cutter, and their opposite side walls are preferably made'fpara'll'el. Because lel, and further, becauseeach slot'lias .paralof the similar location of each slot in the' peno two slots are paral'- lel faces, two adjacent slots 'have theirladfn of the cutter.-

present instance made of a kwidthsomewhat less than the thickness of the bladesattheir outer-ends. Accordingly, theportions of the beinserted in the slots Theblades 11 are made so as to t'snugly are in the 'jacent facesconverging towards Athe center` kes (herein theforwa'rd or lead- Y ing side)as indicated at 18. This construce tion, it will be observed, reduces the space.

between the cutting teeth of adjacent blades'.

Iutilize the convergence of the slots'above referred to in lthe means for securing the blades in'position. T husI providev clamping devices, designated generally by the numeral 19, interposedbetween each-pair of :adja Y cent blades, and shaped to engage with the blades with awedginga'ction so as to clamp themfsimultaneously'in j their respective slots.

bolt 20 provides the body of the wedgingmeans which becomes .eifective on accountof its particular relation tothe cutterbody and,

The vb'oltjlies in a the blades in the slots. hole 21 located midway between two adjasame angular relation to the periphery as the median plane of each slot. The outer end of the bolt yis shaped to provide opposed wedg# ing surfaces'22 and 23 adapted to engage with cent slots and lying in a planefhaving the the opposed surfaces of' adjacent blades '11.

The innerend of the bolt 20 is threaded vand provided with a nut 24 and lock washer 25 seated in a4 countersunk recess 26 formed in the inner periphery of the rim portion 10. Ity will be seen that thetightening of the ,nut 24 of each clamping device 19 serves to secure two blades in their `respective slots vand to loo The construction thus described lends it-Vv Y self readily to economical manufacture.` At

the same ltime accuracy in construction and an equal distribution ofthe clampingedect of each device upon the two blades held thereby is secured.

The manufacturing method preferably employed consists in Vlirst forming the holes 21`Y at the angle of leadV or inclination. vBolts in equidistantly spaced relation and Proper Yare then inserted in the holes and the body is suitably mounted in a milling machine vfor the formation of the slots 17. The nuts 24 on `the bolts are adjusted so that when the bolts" Vare held radiallyoutwardlyfthey occupy their inoperative positions,

The slots are `now milledso as toiintersect Aopposite sides of the bolt holes, and thus the .opposite sides of the bolts inserted therein are vsimultaneously milled, resulting in the lformation of the surfaces 22 and 2?,.Such` surfaces are,vtherefore, coincident withthe opposed sides of the adjacent slots, and because of the converging relation of the slots, the said surfaces 22Vand 23 on the `bolts together form in effect awedging head on the vouter end of each'bolt. The tightening of the nuts 24 onthe bolts produces, it will be Vobserved, an equal clamping eect on both blades, and only a slightly longitudinal movement of the bolt is necessary to Veffect such clamping action.

. While I have disclosed one particular structure ofaV milling cutter and a method by whichv the same may be produced, it is obvious that the invention may be embodied in other forms'of milling cutters and that varivouschanges'may be made by thosegskilled in -v`the art without departing from the Yspirit andscope of the invention as expressed in the appended claims;

vl claim as my invention:

l. Ay milling cutter comprising, a body having an annular rim portion withpairs of slots formed transversely of the periphery of the body and holes passing through said rim portion approximately radially thereof and disposed midway between the slots of each pair, blades inserted in saidV slots, and clamping devices' comprising bolts entered through said holes and each having on one end a wedging head adapted `to coact with the opposed faces of each pair Vof blades and on its other end a tightening nut whereby to actuate the wedging head to clampthe blades.

2. A milling cutter comprising, a body having an annular rim on a web and having a plurality of separate transverse slots formed in the periphery of said Vrim and arranged in pairs, a single blade in each slot and projecting peripherally therefronnand clamping means foreach pair ofbladesrcomprising a wedge having faces engaging the opposed faces of each pair of blades, and means adj ustable Vfrom the'inside ofsaidrim forV actu'- atingthewe'dge to clampthe blades.

A rotary cutter having, in combination, 'anannular body portion having a plurality of separate ltransverse slots in its peripheral 'face'a'ndla pai'rof'spaced holes adjacent to and bothintersecting ,adj acent slots, a single bladein. each o-fsaidslots, a wedge in each hole, and means to.' draw said wedges indej aendentlyof eachother to clamp the blades in the slots. Y

4. .A rotary cutter having, in combination, an annular body portion havingV a pair of transverse slots in its peripheral face, a single cutting bladeinleach of said slots, the body kportion having falso a hole therethrough of greater diameterthan the distance between .adjacent slots to open into each slot,` a bolt `extending throughsaid hole having opposite segmental portions cutaway at its outer end to form iat facescoinciding with the corre' .sponding walls of the slots in one position of the `bolt inthe hole, and a nut on the inner endof said boltl to drawv said bolt into the hole, said flat sides being adapted to clamp against the sides of the blades in the slots when drawn inwardly.

5. A rotary cutter having, in combination, an annular bodyportion having a plurality of sets of holes similarly located therein near the peripherythereof', the holes -of each set being spaced transversely of the body portion, andhaving a: plurality of transverse slots with adjacent slots intersecting one set of holes on opposite'sides, a bolt in each of said holes having a wedge-shaped end, the faces ofthe ,wedge being coincident with the walls of the adjacent slots in one position of th'e bolt in fits hole, a cutting blade litting into each slot, and means to draw said bolts independently of each other to wedge the blades in the slots.

6. VA rotary cutter having, incombination, an annular body portion, a Vcentral web supporting said body'portion thereby forming shoulders on opposite sides of the web, the body portion having a plurality of pairs of holes extending therethrough from the periphery to said shoulders, and having alsova plurality of slots vin the periphery of the body portion"transversely thereof, the arrangement being lsuch that two adjacent Aslots intersect a pair of holesV on opposite sides, a bolt in each hole having Wedge faces at the outer end Acorresponding to the Vfaces of the. slots at the intersection with the hole, a

blade in each slot, and a nut on the inner-'end of each bolt at the shoulder of the body portion to draw the wedge end of the bolt, whereby to clamp the blades in the slots.-

7 A rotary cutter having, in combination,

an annular body portion, a central web supporting said body portion, and forming with the body portion a pair of shoulders on oppo- Y site sides of the web, the body portion having a plurality of pairs of holes extending,l through from the periphery thereof to said shoulders, and having also a plurality of slots in the periphery of theV body portion transversely thereof, each -slot being disposed so as to intersect a pair of holes, a boltin each hole, a blade in each slot, each bolt having its side adjacent the outer end thereof cut away to provide a wedging surface adapted to engage the blade in the slot, and a nut onVV the inner end of each bolt at the shoulder of the body portion to draw the bolt whereby f to clamp the blade in the slot.

8. A rotary cutterhaving, in combination,

an annular body portion, a central web supporting said body portion thereby forming shoulders on opposite sides of the web, said body portionv having a plurality of sets of transversely spaced holes extending therethrough from said'shoulders to the periphery, and having a plurality of pairs of transverse slots respectively intersecting said sets' of holes on opposite sides, a cutting blade t ting in each slot, a bolt in each of said holes having a wedge-shaped end, and a nut on the inner end of each bolt bearing against one of said shoulders for drawing the bolt inwardly to wedge the blades in the slots, vthe holes of each set being convergent toward the periphery of the body portion.

9. A milling cutter having blades inserted in slots in the periphery of the cutter, there being a single blade in each slot, wedge members movable in holes connecting each pair of adjacent slots, the blades in said slots and the wedge member therebetween being interrelated as wedges to each other whereby two blades and said wedge member are wedged between the outer faces yof each pair of slots, each wedge member being formed on the outer end of a bolt, and means on'the inner end of each bolt for adjusting said bolt.

In testimony whereof, I have hereunto `afxed my signature.

JOHN EDGAR.

CERTIFICATE OF CORRECTION.

Patent No. 1,855,511. April 26, 1932.

JOHN EDGAR.

lt is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 3, line 40, beginning with the numberl and words "9. A. milling" strike out all to and including "said boit." in line 51, comprising claim 9; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.v

Signed and sealed this 12th day of July, A. D. 1932.

M. J. Moore, (Seal) Acting Commissioner of Patents. 

